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Note 12 - Self-Insurance | 12 Months Ended
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Dec. 31, 2022
Notes to Financial Statements |
Self Insurance [Text Block] | (12) SELF INSURANCE We self-insure our underground mining equipment. Such equipment is allocated among seven mining units dispersed over 10 miles. The historical cost of such equipment was approximately $280 million and $260 million as of December 31, 2022 and December 31, 2021, respectively. Restricted cash of $3.4 million and $3.3 million as of December 31, 2022, and December 31, 2021, respectively, represents cash held and controlled by a third party and is restricted for future workers’ compensation claim payments.

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